Patent GB-191516149-A (GB)
Title: Arrangement for Phonographically Recording and Reproducing Telephonic Message.
Inventor: SEELAU FRANZ
Filed: 1915-11-16
Abstract: 16,149. Seelau, F., and Newman, A. M. Dec. 5, 1914, [Convention date]. Telephone signals, reconding ; electric and magnetic sound-boxes ; sound-box cases ; tool arms and mountings ; feed motions.-A phonograph arranged for recording telephone messages is provided with interchangeable electro-magnetic and ordinary soundboxes, so that the machine may alternatively be used for reproducing or as an office dictaphone. The diaphragm 20, Fig. 3, preferably of magnetic material, is mounted in a casing 19 secured to a bracket 18, which can rock slightly around a sleeve 7 in order to change from the recording to the reproducing position and is fed in a direction parallel to the record axis by a screw 6. Within an upwardly-extending circular flange 22 on the diaphragm case, an electro-magnetic sound-box 50 is removably fitted by a bayonet-joint, the pole-pieces 41 of the magnet being adjustable relatively to the diaphragm 20 by a screw 43 enclosed by a spring. When the machine is required to reproduce a recorded telephone message, or for use as a dictaphone, an ordinary sound-box 52, Fig. 2, fitted with a speaking and listening tube or horn 51 is substituted for the electro-magnetic box 50. The removal of the sound-box 50 from the flange 22 may automatically operate a switch to disconnect it from the telephone circuits ; or a switch lever 48 may be provided with a tray 49, Fig. 2, for receiving the electro-magnetic sound-box 50 when it is not in use. The feed-screw 6 is engaged by a spring-pressed sliding pin 10 guided in a vertical arm 16, and the pin may be raised and lowered by a cam-depression 12 on a hand-operated annulus 13. When the pin is disengaged, the stylus lever is raised out of contact with the record by a lug 30 on the annulus. The column 16 is prevented from rotary movement by a longitudinal rod 17 and is provided at its upper part with a sector-shaped bracket 34. The bracket 18 carrying the sound-box 19 has a pointer to indicate on the sector 34 whether the sound-box is in the recording or reproducing position, and a spring pin 35 locks it in either position. The stylus lever 26 carries a cutting or recording tool 27 at its outer end and a rounded reproducing-tool 28 at an intermediate point, and is coupled by a rod 29 at its opposite end to the diaphragm 20. It is pivoted centrally on an arm 25 hinged to a member 24 having a swivelling connexion to the bracket 18. The arm 25 is weighted by a pivoted block 31. When the sound-box is in the raised or recording position, as shown in Fig. 3, the swivelling member 24 is held by the engagement of a pair of pins 36 with a resilient cross-piece 37, and the weight 31 is rendered inoperative by the engagement of a projection 32 with a fixed lug 33. When the sound-box is lowered into the reproducing position, shown in Fig. 4, the tool 28 engages the record in place of the cutting-tool 27, the weight 31 becomes operative, and the cross-piece 37 is withdrawn from contact with the pins 36, leaving the arm 25 free to swivel as the tool passes over irregularities in the record grooves.